Okay, so I bought this system a couple months ago, read through it, started drafting a review, lost my hard drive, and now I'm starting it all over from scratch. Criminey. Anyway, so yes the Adventurer Conqueror King System (ACKS) is one of those D&D old school renaissance (OSR) systems. However, that's not why I bought it. I bought it because reportedly featured a well-designed "end game" for high level characters, including economic and political elements. I was hoping that it might be adaptable for my Old School Hack/Fictive Hack game if any (surviving) players get to higher levels. Since ACKS is a mighty tome of gaming richness I'm breaking this review into two parts (or maybe three).
So like most RPGs, ACKS starts out with character generation. Since it is an OSR system it has a class-based system. For humans there are the classic fighter, mage, cleric, and thief, but also four campaign classes, the assassin, bard, bladedancer, and explorer. I particularly liked the bladedancer. Also typical for an OSR system, the demi-humans (elves and dwarves) have their own racial classes. However I was glad to see that they at least give each race two classes instead of a single stereotyped one, which is a definite improvement. The dwarves get the Vaultguard and the Craftpriest; the elves the Spellsword and the Nightblade.
So far so good, but note that none of these classes go to 20th level. The highest level in ACKS is 14th. This tames the usual D&D power curve and I'm on board with that. However, only the human classes go up to 14th. All the demi-human ones stop short of that: vaultguard just short of it at 13th, nightblade at 11th, but craftpriest and spellsword only at 10th. That certainly provides a strong incentive to avoid playing the latter three classes. Why are these classes arbitrarily penalized? I have no idea. People who like to play dwarf and elf characters certainly won't think it's a great idea.
ACKS has a system of proficiencies, which are like a blend of the feats and skills you find in D&D 3.x and Pathfinder. Proficiencies are gained at certain levels, which varies from class to class, and most can only taken once. I rather like that the feats and skill are essentially blended into one system. It's simpler, easier to keep track of on the character sheet, and avoids a lot of the fiddly math of allocating new skill points each level.
But then we get to the first of the material for which I bought ACKS: hirelings (henchmen, mercenaries, and specialists). The early editions of D&D envisioned characters eventually becoming powers in the land, with fighters building a castle, wizards a tower, etc. And along the way they would hire or recruit NPCs to help them. At any given time and place the number of hirelings will be limited and they may prove difficult to recruit, based on the local hiring market and the PC's charisma (so you may be sorry you used it as your "dump stat"). Hiring people is something PCs will have to do in an ACKS campaign and the rules here provide enough detail without getting bogged down. So far so good.
Next, I was very pleasantly surprised to see that for spellcasting ACKS ditched the miserable spell-slot system which has plagued D&D and its derivatives for lo these many years. (Actually, I almost just skipped this section on the assumption that it would be spell slots.) In ACKS there is no tedious spell preparation time on the part of the players. Spellcasters know certain spells and they can cast anything they know, limited by the total number of spells of a given level castable per day. Nice. I also like that they have exactly 10 (divine) or 12 (arcane) spells per spell level so you can easily determine a random spell with a quick die roll. They also discuss limiting the cleric's spell lists based on deity, which is something I feel D&D desperately needs, but unfortunately only provide one example of a limited list. I think most GMs could take that example and work out their own deity-specific lists, but I wish they'd done more examples to help people out. (Perhaps that will be covered in future ACKS books, or on a blog somewhere...)
So that's part one. Still to come: adventures, campaigns, monsters, treasures, and secrets.